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SRealIO

REAL (single-precision floating-point) I/O following the ISO 10514 Modula-2 standard. Provides three output formats: scientific notation, fixed-point, and general-purpose. This is the ISO-style equivalent of RealInOut.

Available in PIM4 mode (the default). No special flags needed.

Procedures

Output

PROCEDURE WriteFloat(r: REAL; sigFigs: CARDINAL; w: CARDINAL);

Write r in scientific notation (e.g., 1.414E+00) with sigFigs significant figures, right-justified in a field of width w. Use this when you need consistent exponential notation.

PROCEDURE WriteFixed(r: REAL; place: INTEGER; w: CARDINAL);

Write r in fixed-point format with place digits after the decimal point, right-justified in width w. Use this for tabular output where you want a consistent number of decimal places.

Example: WriteFixed(3.14159, 2, 10) prints " 3.14".

PROCEDURE WriteReal(r: REAL; w: CARDINAL);

Write r in general format (like C's %g), right-justified in width w. The format is automatically chosen: fixed-point for moderate values, scientific for very large or very small values.

Input

PROCEDURE ReadReal(VAR r: REAL);

Read a REAL value from stdin. Accepts decimal notation (3.14), scientific notation (1.0E-3), and integer notation (42, which is read as 42.0).

Example

MODULE SRealIODemo;
FROM STextIO IMPORT WriteString, WriteLn;
FROM SRealIO IMPORT WriteFloat, WriteFixed, WriteReal;
FROM MathLib IMPORT sqrt;

VAR r: REAL;

BEGIN
  r := sqrt(2.0);

  WriteString("General:    ");
  WriteReal(r, 12); WriteLn;

  WriteString("Fixed 4dp:  ");
  WriteFixed(r, 4, 12); WriteLn;

  WriteString("Scientific: ");
  WriteFloat(r, 6, 12); WriteLn
END SRealIODemo.